Creates downward 45 degree angle stripe pattern.
Alter viewport to change size of stripes
<DrawingBrush Stretch="UniformToFill" ViewportUnits="Absolute" Viewport="0,0,10,10" TileMode="Tile">
<DrawingBrush.Drawing>
<DrawingGroup>
<DrawingGroup.Children>
<GeometryDrawing Brush="Black">
<GeometryDrawing.Geometry>
<GeometryGroup FillRule="Nonzero">
<PathGeometry>
<PathFigure StartPoint="0,0">
<LineSegment Point="100,0"/>
<LineSegment Point="100,100"/>
<LineSegment Point="0,100"/>
</PathFigure>
</PathGeometry>
</GeometryGroup>
</GeometryDrawing.Geometry>
</GeometryDrawing>
<GeometryDrawing Brush="#FF404040">
<GeometryDrawing.Geometry>
<GeometryGroup FillRule="Nonzero">
<PathGeometry>
<PathFigure StartPoint="0,0">
<LineSegment Point="25,0"/>
<LineSegment Point="100,75"/>
<LineSegment Point="100,100"/>
<LineSegment Point="75,100"/>
<LineSegment Point="0,25"/>
<LineSegment Point="0,0"/>
</PathFigure>
<PathFigure StartPoint="75,0">
<LineSegment Point="100,25"/>
<LineSegment Point="100,0"/>
</PathFigure>
<PathFigure StartPoint="0,75">
<LineSegment Point="25,100"/>
<LineSegment Point="0,100"/>
</PathFigure>
</PathGeometry>
</GeometryGroup>
</GeometryDrawing.Geometry>
</GeometryDrawing>
</DrawingGroup.Children>
</DrawingGroup>
</DrawingBrush.Drawing>
</DrawingBrush>
Alternatively you could bind the scale transform to the height and width of the control using multibinding. Then with a converter, you alter the scale to the max of height or width, then the stripes will remain the same size.